Psychopathy is a personality disorder comprised of a constellation of interpersonal, affective and behavioral characteristics. Individuals with psychopathy are responsible for a disproportionate amount of civil disruption, both criminal and noncriminal. The societal cost of psychopathy, including fiscal and emotional components, rivals those of other major mental illnesses of similar prevalence (~1% general population). However, relative to other major disorders (e.g., schizophrenia), little is known about the neurocognitive systems implicated in psychopathy. Recent small scale electrophysiological and hemodynamic imaging studies done by the primary investigator have shown that criminal psychopathy is associated with functional abnormalities in the paralimbic system during performance of affective, error-monitoring, and salient stimulus (e.g., oddball) processing tasks. The primary paralimbic structures that appear to be implicated include the amygdala, orbital frontal cortex, anterior superior temporal gyrus, rostral and caudal anterior cingulate, and posterior cingulate. The purpose of the present proposal is to test the paralimbic hypothesis of psychopathy in samples drawn from community based populations of ethically diverse males and females from varied socio-economic backgrounds. High temporal resolution electrophysiological techniques and high spatial resolution hemodynamic imaging will be used to map the functional neural architecture associated with affective, error-monitoring, and salient stimulus processing tasks in groups stratified by psychopathy scores. The ultimate aim of the proposed project is to obtain a more complete understanding of the brain systems implicated in psychopathy, and secondarily, to begin to understand how brain function relates to psychopathic symptomology. At the conclusion of the study, data will be available to characterize dysfunctional neuroanatomy in psychopaths not drawn exclusively from incarcerated samples. The data also will permit an examination of psychopathy-specific paralimbic brain function abnormalities along gender and socioeconomic lines, exploration of how brain function abnormalities relate to psychopathy symptom subtypes, and will provide data on the inter-relationship of functional brain abnormalities in psychopathy and alcohol and substance disorders.